This invention relates generally to the fabrication and utilization of micron-scale structures. More particularly, this invention relates to a non-interlocking adhesive microstructure.
There is an ongoing need for improved adhesives. Improved adhesives have applications ranging from everyday aspects of life (e.g., tape, fasteners, and toys) to high technology (e.g., removal of microscopic particles from semiconductor wafers, transporting fiber optic devices, and assembly of sub-mm mechanisms, particularly those including micro-fabricated components, or components that cannot tolerate grippers, adhesives, or vacuum manipultors).
Adhesive mechanisms in nature have been studied, but have not been fully understood or exploited. For example, Geckos are exceptional in their ability to rapidly climb up smooth vertical surfaces. The mechanism of adhesion used in Geckos, Anolis lizards, some skinks, and some insects, has been debated for nearly a century.
While some prior work has identified the morphology of seta used by Geckos and other insects, this prior work does not identify how the seta operates. In addition, this prior work fails to identify how to use a seta to perform useful work.
It would be highly desirable to identify and exploit the adhesive force mechanism utilized by Geckos and other insects. Such information could result in the utilization of new adhesive microstructures and the fabrication of such structures.
The invention includes a method of forming an adhesive force. The method includes the steps of removing a seta from a living specimen, attaching the seta to a substrate, and applying the seta to a surface so as to establish an adhesive force between the substrate and the surface.
The invention also includes a method of establishing a adhesive microstructure. The method includes the step of applying a seta to a surface with a force perpendicular to the surface. The seta is then pulled with a force parallel to the surface so as to preload an adhesive force of the seta.
The invention also includes a method of fabricating an adhesive microstructure. The fabrication technique includes fabricating an array of shafts and then forming spatulae on the array of shafts.
The invention also includes a fabricated microstructure with a shaft having a length of less than 500 microns. The shaft has a diameter of between 0.01 and 0.1 times the length of the shaft. An array of spatulas is formed at an end of the shaft. The array of spatulae has a width of less than 10 microns. Individual spatula of the spatulae include a terminal end with an extended surface, such as a paddle, a curved segment of a sphere, or a flattened segment of a sphere.